Apologies. I hope that was not me as the reviewer does not have access to that image. This prompted me to dig deeper to find exactly the file that was returned by the reviewer. I thought I had trashed it so went away back. All I have done now is to rename this file to 39 Floyd Review Returned (8711kb) and put it in Onedrive at https://1drv.ms/w/s!Aj3Y_ibknUwKhVVh3uxOyYipctx2 Compare this with the original I sent, which I am sure has not been modified, 39 Floyd Review (356kb). I do have a tiif and jpeg version of that figure so I have just tested by making a copy of this paper and putting in the tiff version. Save that and the file size is 342kb. So next I have taken the monster file and replaced the graphic in that with the tiff copy. I also found that "File/Options/Advanced/Do not compress images in file" had been ticked. It was unticked in the small file I sent out.
So, the image was certainly changed. There is evidence that the file was used on a MAC. I now see how to change it back again. Replacement of the image is necessary. Simply going into the oversize document and unticking the box and saving does not reduce the size.
I hope all this is helpful.